Reciprocal control of ADAM17/EGFR/Akt signaling and miR-145 drives GBM invasiveness

MiR-145-5p reduced ANG II-induced ACE2 shedding and the inflammatory response in alveolar epithelial cells by targeting ADAM17 and inhibiting the AT1R/ADAM17 pathway

The excessive elevation of angiotensin II (ANG II) is closely associated with the occurrence and development of aortic dissection (AD)-related acute lung injury (ALI), through its binding to angiotensin II receptor type I (AT1R). MiR-145-5p is a noncoding RNA that can be involved in a variety of cellular physiopathological processes. Transfection with miR-145-5p was found to downregulated the expression of A disintegrin and metalloprotease 17 (ADAM17) and reduced the levels of angiotensin-converting enzyme 2 (ACE2) in lung tissue, while concurrently increasing plasma ACE2 levels in the AD combined with ALI mice. ADAM17 was proved to be a target of miR-145-5p. Transfection with miR-145-5p decreased the shedding of ACE2 and alleviated the inflammatory response induced by ANG II through targeting ADAM17 and inhibiting the AT1R/ADAM17 pathway in A549 cells. In conclusion, our present study demonstrates the role and mechanism of miR-145-5p in alleviating ANG II-induced acute lung injury, providing a new insight into miRNA therapy for reducing lung injury in patients with aortic dissection.

miR-145 Alleviates Smooth Muscle Cell Phenotype Transition via ADAM17-Mediated ACE2 Shedding

It has been shown that miR-145 is involved in the differentiation of vascular smooth muscle cells (VSMCs) and may regulate vascular remodeling. However, the molecular mechanisms behind these pathological processes in hypertension are not fully elucidated. The present study was to examine whether miR-145 modulates phenotypic transformation of VSMCs under normal state and synthetic state and to explore the possible role of ADAM17-mediated ACE2 shedding and ACE2-Ang-(1-7)-Mas receptor axis. Wistar rats were fed with high-sucrose/high-fat diet for 30 weeks to establish a metabolic hypertension animal model. VSMCs were cultured and treated with Ang II with or without miR-145 mimics or miR-145 inhibitor. Results showed the expression of contractile markers α-SMA and SM22α, miR-145, ACE2, and Mas receptor reduced in the thoracic aorta of metabolic hypertensive rats (MHRs), while that of synthetic marker OPN increased as compared to the control group. In in vitro study, miR-145 inhibitor inhibited the expression of α-SMA, SM22α, ACE2, Mas receptor, and the Ang-(1-7) excretion and induced the expression of synthetic markers OPN, EREG, and MMP2. However, miR-145 mimic produced opposite effects on the VSMCs. In addition, in the synthetic VSMC induced by Ang II, miR-145 inhibitor partially reversed the induced expression of OPN, EREG, and MMP2 by Ang II, while further decreasing the expression of α-SMA and SM22α and ACE2-Ang-(1-7)-Mas receptor. Cotreatment with ADAM17 siRNA partially reversed the inducible effect of miR-145 inhibitor on the EREG and MMP2, induced Ang-(1-7) excretion, and upregulated ACE2 and Mas receptor expression. In conclusion, miR-145 alleviates phenotype transition from contractile to synthetic type via ADAM17-mediated ACE2 shedding in VSMCs and retains the activation of ACE2-Ang-(1-7)-Mas axis, which may benefit the vascular structural remodeling in the metabolic hypertension.

ADAM17 Confers Temozolomide Resistance in Human Glioblastoma Cells and miR-145 Regulates Its Expression

Glioblastoma (GBM) is a malignant brain tumor, commonly treated with temozolomide (TMZ). Upregulation of A disintegrin and metalloproteinases (ADAMs) is correlated to malignancy; however, whether ADAMs modulate TMZ sensitivity in GBM cells remains unclear. To explore the role of ADAMs in TMZ resistance, we analyzed changes in ADAM expression following TMZ treatment using RNA sequencing and noted that ADAM17 was markedly upregulated. Hence, we established TMZ-resistant cell lines to elucidate the role of ADAM17. Furthermore, we evaluated the impact of ADAM17 knockdown on TMZ sensitivity in vitro and in vivo. Moreover, we predicted microRNAs upstream of ADAM17 and transfected miRNA mimics into cells to verify their effects on TMZ sensitivity. Additionally, the clinical significance of ADAM17 and miRNAs in GBM was analyzed. ADAM17 was upregulated in GBM cells under serum starvation and TMZ treatment and was overexpressed in TMZ-resistant cells. In in vitro and in vivo models, ADAM17 knockdown conferred greater TMZ sensitivity. miR-145 overexpression suppressed ADAM17 and sensitized cells to TMZ. ADAM17 upregulation and miR-145 downregulation in clinical specimens are associated with disease progression and poor prognosis. Thus, miR-145 enhances TMZ sensitivity by inhibiting ADAM17. These findings offer insights into the development of therapeutic approaches to overcome TMZ resistance.

Immunomodulatory role of metalloproteinase ADAM17 in tumor development

ADAM17 is a member of the a disintegrin and metalloproteinase (ADAM) family of transmembrane proteases involved in the shedding of some cell membrane proteins and regulating various signaling pathways. More than 90 substrates are regulated by ADAM17, some of which are closely relevant to tumor formation and development. Besides, ADAM17 is also responsible for immune regulation and its substrate-mediated signal transduction. Recently, ADAM17 has been considered as a major target for the treatment of tumors and yet its immunomodulatory roles and mechanisms remain unclear. In this paper, we summarized the recent understanding of structure and several regulatory roles of ADAM17. Importantly, we highlighted the immunomodulatory roles of ADAM17 in tumor development, as well as small molecule inhibitors and monoclonal antibodies targeting ADAM17.

Analysis of A Disintegrin and Metalloprotease 17 (ADAM17) Expression as a Prognostic Marker in Ovarian Cancer Patients Undergoing First-Line Treatment Plus Bevacizumab

To find prognostic factors for advanced ovarian cancer patients undergoing first-line therapy with carboplatin, paclitaxel and bevacizumab, we investigated the expression of a disintegrin and metalloprotease 17 (ADAM17) in cancer tissues. ADAM17 has been involved in ovarian cancer development, progression and cell resistance to cisplatin. Tissue microarrays from 309 ovarian cancer patients enrolled in the MITO16A/MANGO-OV2 clinical trial were analyzed by immunohistochemistry for ADAM17 protein expression. Intensity and extent of staining were combined into a semi-quantitative visual grading system (H score) which was related to clinicopathological characteristics of cases and the clinical outcome of patients by univariate and multivariate Cox regression models. ADAM17 immunostaining was detected in most samples, mainly localized in the tumor cells, with variable intensity across the cohort. Kaplan–Meier survival curves, generated according to the best cut-off value for the ADAM17 H score, showed that high ADAM17 expression was associated with worse prognosis for PFS and OS. However, after the application of a shrinkage procedure to adjust for overfitting hazard ratio estimates, the ADAM17 value as prognostic factor was lost. As subgroup analysis suggested that ADAM17 expression could be prognostically relevant in cases with no residual disease at baseline, further studies in this patient category may be worth planning.

Comprehensive analysis: Necroptosis-related lncRNAs can effectively predict the prognosis of glioma patients

Glioma is the most common and fatal primary brain tumor in humans. A significant role for long non-coding RNA (lncRNA) in glioma is the regulation of gene expression and chromatin recombination, and immunotherapy is a promising cancer treatment. Therefore, it is necessary to identify necroptosis-related lncRNAs in glioma. In this study, we collected and evaluated the RNA-sequencing (RNA-seq) data from The Cancer Genome Atlas (TCGA, https://www.ncbi.nlm.nih.gov/, Data Release 32.0, March 29, 2022) glioma patients, and necroptosis-related lncRNAs were screened. Cox regression and least absolute shrinkage and selection operator (LASSO) analysis were performed to construct a risk score formula to explore the different overall survival between high- and low-risk groups in TCGA. Gene Ontology (GO) and pathway enrichment analysis (Kyoto Encyclopedia of Genes and Genomes (KEGG)) were performed to identify the function of screened genes. The immune correlation analysis showed that various immune cells and pathways positively associated with a patient’s risk score. Furthermore, the analysis of the tumor microenvironment indicated many immune cells and stromal cells in the tumor microenvironment of glioma patients. Six necroptosis-related lncRNAs were concerned to be involved in survival and adopted to construct the risk score formula. The results showed that patients with high-risk scores held poor survival in TCGA. Compared with current clinical data, the area under the curve (AUC) of different years suggested that the formula had better predictive power. We verified that necroptosis-related lncRNAs play a significant role in the occurrence and development of glioma, and the constructed risk model can reasonably predict the prognosis of glioma. The results of these studies added some valuable guidance to understanding glioma pathogenesis and treatment, and these necroptosis-related lncRNAs may be used as biomarkers and therapeutic targets for glioma prevention.

Prognostic Significance of ADAM17 for Gastric Cancer Survival: A Meta-Analysis

Background and objectives: The prognostic role of a disintegrin and metalloproteinase (ADAM) 17 has been widely assessed in gastric cancer. However, the results are inconsistent. We performed a meta-analysis to evaluate the prognostic significance of ADAM17 and its association with clinicopathological parameters. Methods: The databases of PubMed, Web of Science, and Embase were searched for relevant articles published up to April 2020. The reported hazard ratios (HRs) and odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were pooled to evaluate the strength of the association. Stata 12.1 was used to perform statistical analyses. Results: Seven studies, including 1757 patients, were screened for the meta-analysis. Compared with the high ADAM17 expression group, the pooled HR was higher in the low ADAM17 expression group (HR = 2.04, 95% CI 1.66–2.50; I² = 18.1%; p = 0.299). High ADAM17 expression was also related to the tumor node metastasis (TNM) stages (OR = 4.09, 95% CI 1.85–9.04; I² = 84.1%; p = 0.000), lymph node metastasis (OR = 3.08, 95% CI 1.13–8.36; I² = 79.7%; p = 0.007), and ages (OR = 1.65, 95% CI 1.24–2.21; I² = 0%; p = 0.692) of the gastric patients. Conclusions: This meta-analysis revealed that ADAM17 is a significant biomarker for poor prognosis in gastric cancer.